Human hair becomes soiled due to its contact with the surrounding atmosphere and, to a greater extent, from sebum secreted by the head. The build-up of the sebum causes the hair to have a dirty feel and an unattractive appearance. The soiling of the hair necessitates it being shampooed with frequent regularity.
Shampooing the hair cleans by removing excess soil and sebum. However, the shampooing process has disadvantages in that the hair is left in a wet, tangled and generally unmanageable state. A variety of approaches have been developed to alleviate the after-shampoo problems. These range from the inclusion of hair conditioning aids in shampoos to post-shampoo application of hair conditioners, i.e., hair rinses. Hair rinses typically work by depositing a polymeric film or other material onto the hair. However, such solutions to a very prevalent problem have not been fully satisfactory. For one thing, hair rinses are generally liquid in nature and must be applied in a separate step following the shampooing, left on the hair for a length of time, and rinsed with fresh water. This, of course, is time consuming and is not convenient.
While shampoos have been disclosed which contain conditioning aids, they have not been totally satisfactory for a variety of reasons. One problem relates to compatibility problems between good cleaning anionic surfactants and the fatty cationic agents which are good conditioning agents. This has caused other surfactants such as nonionics, amphoterics and zwitterionics to be examined by workers in the field. Many of these efforts are reflected in patents issued in the conditioning shampoo area. See for example U.S. Pat. No. 3,849,348, Nov. 19, 1974 to Hewitt; U.S. Pat. No. 3,990,991, Nov. 9, 1961 to Gerstein; and U.S. Pat. No. 3,822,312, July 2, 1974 to Sato.
The use of these other surfactants solved many of the compatibility problems but still did not provide complete answers in all areas. For instance cationic conditioners may not deliver the desired level of softness desired by users. Materials which can provide increased softness are silicones, both those which are soluble as well as insoluble in the shampoo matrix.
Silicones in shampoo compositions have been disclosed in a number of different publications. Such publications include U.S. Pat. No. 2,826,551, Mar. 11, 1958 to Geen; U.S. Pat. No. 3,964,500, June 22, 1976 to Drakoff; U.S. Pat. No. 4,364,837, Dec. 21, 1982 to Pader; British Pat. No. 849,433, Sept. 28, 1960 to Woolston; U.S. Pat. No. 4,341,799, July 27, 1982 to Good, and U.S. Pat. No. 4,465,619, Aug. 14, 1984 to Boskamp. While these patents disclose silicone containing compositions, they also do not provide answers to all of the problems encountered in making a totally satisfactory product. One unsolved problem is that of keeping a dispersed, insoluble, non-volatile silicone material suspended and the total product stable while still providing satisfactory shampoo performance. A variety of materials have been included in silicone containing shampoos for purposes of thickening and stabilization but totally satisfactory solutions are lacking. It has been surprisingly found that compositions comprising specific components can provide stable compositions without interfering unduly with the deposit of the silicone material onto the hair and other shampoo functions.
It is an object of the present invention to provide a stable silicone containing conditioning shampoo.
It is a further object of the present invention to provide silicone shampoo compositions containing xanthan gum.
It is a further object of the present invention to provide shampoos which provide good conditioning (e.g., ease of combing, softness, feel, etc.) to hair.
It is a further object of the present invention to provide an improved method of shampooing and conditioning hair.
These and other objects will become readily apparent from the detailed description which follows.
Unless otherwise indicated, all percentages and ratios herein are by weight.